heat up , both metals
expand, but one does it faster than the other. The strip
bends and
connects with a switch, which
turns off the power supply. When the strip
cools down , the metals
contract and
the switch is
disconnected . (1 word)
2. This object has several
component parts , most of which are made of plastic. A disc inserted into the
object
spins quickly. At the same time a thin beam of light
strikes the disc and
converts digital symbols
into sounds. These sounds can be
increased or
decreased in volume by means of a button or dial.
(3 words)
3. Liquid and gas are
compressed in a hard metal tube. This can be
released by
pushing or
squeezing a
button which
opens a valve. When the liquid-gas combination
leaves the tube and is mixed with
oxygen, it rapidly
expands . (1 word)
4. This object is mainly
made of aluminium. As it
moves forward, air
flows over two horizontal sections.
As it
accelerates , a vacuum is
formed over the horizontal sections and the object is pulled into the air
by the force of this vacuum. (1 word)
5. This object consists of two main parts; one is made mainly of plastic and metal, the other is made
mainly of glass. Light
enters the glass section and a small door in the device
